Literally on the last page of the ATSDR MRL methodology,the authors clarify the esssential point – I am not a toxicologist so I just read this, which makes my interpretation of MRLs inaccurate – exceedence of the MRLs are NOT assured to have adverse effects. I over-stated the science behind the MRL. Regardless I will not take this post down, because readers should know that I acknowledge mistakes in judgement, and because the MRL is still a useful tool and a precautionary approach suggests that the use if the word “safe” is misleading:

MRLs are intended to serve as a screening tool to help public health professionals decide where to look more closely. They may also be viewed as a mechanism to identify those hazardous waste sites or other hazardous substance exposures that are not expected to cause adverse health effects. The MRLs are set below levels that, based on current information, might cause adverse health effects in the people most sensitive to such substance-induced effects (Barnes and Dourson, 1988; USEPA, 1990). Most MRLs contain some degree of uncertainty because of the lack of precise toxicological information on the people who might be most sensitive (e.g., infants, elderly, and nutritionally or immunologically compromised) to the effects of hazardous substances. A conservative (i.e., protective) approach is used to address these uncertainties, consistent with the public health principle of prevention. Although human data are preferred, MRLs often must be based on results of animal studies because relevant human studies are lacking. In the absence of evidence to the contrary, it is assumed that humans are more sensitive than animals to the effects of hazardous substances, and that certain persons may be particularly sensitive. Thus, the resulting MRL may be as much as a hundredfold below levels shown to be nontoxic in laboratory animals. Exposure to a level above the MRL does not mean that adverse health effects will occur. - end clarification

Air monitoring data in Paulsboro after the toxic train wreck were 10 -12 times higher than “safe” health effects levels set by federal health authorities.

According to federal scientists, the health risks of concern to these levels of exposure are developmental effects in children and the developing fetus.

Paulsboro air monitoring data were just posted on line, showing levels of vinyl chloride from November 30 – December 11.

At the time, State DEP and Coast Guard officials were assuring the public that the air was “safe” and that respiratory problems, coughing and light-headedness were the problems that residents exposed to the hazardous chemicals may experience.

The data just released show that on November 30, the level detected in the community was 1.2 ppm; on December 3 the level detected in the community was 5.6 ppm and on December 4 the level was 9.438 ppm.

Levels in the evacuation zone were higher, from 3 – 8.58 ppm during this period.

The most scientifically credible source of information for assessing the “safety” of these air monitoring levels is produced by the federal Agency for Toxic Substances and Disease Registry (ATSDR). In an effort to get the best information out to the public, I excerpted and provided a link to ATSDR information on my first post on this story on November 30.

The federal Agency for Toxic Substance and Disease Registry (ATSDR) publishes what are known as “minimal risk levels” (MRLs). In judging if the air is “safe”, the Paulsboro monitoring results should be compared to ATSDR MRLs.

In order to address the congressional mandate to ascertain levels of exposure that present a significant risk to human health, ATSDR develops minimal risk levels (MRLs) for priority hazardous substances most frequently found at hazardous waste sites. The MRLs are health guidance values derived based on the most sensitive non-cancer adverse health endpoints.

An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse noncancer health effects over a specified duration of exposure. …

MRLs are derived when reliable and sufficient data are available to identify the target organ(s) of effect, or the most sensitive health effect(s) for acute (1-14 days), intermediate (15-364 days), and chronic (365 days and longer) exposure durations and for the oral and inhalation routes of exposure to the substance. …

MRLs are derived using the no-observed-adverse-effect level/uncertainty factor (NOAELlUF) approach that ensures that they are below levels that might cause detectable adverse health effects in the people most sensitive to such effects.

Exceedence of the MRLs equates to exposure with an “appreciable risk” of “detectable adverse effects” in children, the most sensitive population.[Note: these are for non-cancer effects. As I wrote, vinyl chloride is a potent carcinogen.]

Here are the ATSDR MRL’s for inhalation of vinyl chloride: for acute exposure (1-14 days) the MRL is 0.5 ppm. The MRL for an intermediate exposure (lasting 15 – 365 days) is more than 10 times lower, 0.03 ppm

The health effects of concern resulting from exposure to vinyl chloride are developmental effects. Children are far more susceptible to vinyl chloride exposures. Developmental effects are define as:

As defined in the ATSDR (1995a) guidance, develop­ mental toxicity is any adverse effect on the developing organism from implantation through prenatal develop­ment or postnatally to the time of sexual maturation. These effects can result from exposure prior to implan­tation (either parent) or during prenatal and postnatal development. Systemic, immunological, or neruological effects seen in the developing organism prior to sexual maturity may be considered secondary to adverse de­ velopmental effects.

1. Is the air safe?

Yes – Air monitoring results indicate that the air in the community is safe. Before schools are re-opened, the air inside and outside the schools will be tested to confirm that they are safe to enter. Similarly, upon the homeowner’s request, we can test the air in homes in the area to confirm that they are also safe to re-enter. …

7. Am I at risk for long-term health effects?

No – Short-term exposures to the low levels of vinyl chloride that may have occurred before the evacuation do not present a long-term health risk to residents in the area. Vinyl chloride is rapidly removed from the body after exposure is over.

There is no indication that exposures such as those that may have occurred in the evacuated community after the derailment increase the risk of cancer or any other long-term health effects; however, vinyl chloride has been shown to cause cancer in people exposed in the workplace to high concentrations for many years.

That is a false , incomplete, and misleading statement.

The air was NOT safe because it exceeded the ATSDR MRLs by 10 – 20 times.

In addition to respiratory effects, children and developing fetus’ in the community that were exposed to these levels were put at risk (of cancer and non-cancer effects especially in susceptible populations, like children).

Respiratory problems, coughing and light-headedness were the problems that residents exposed to the hazardous chemicals may experience,“but there is no long-term effect,” said Lawrence Ragonese, spokesman for the state Department of Environmental Protection.

“We are being very conservative because we are worried about your health,” he said.

As I wrote on December 6,that was a false, incomplete, and misleading statement. The levels detected exceeded ATSDR MRLs and were not “safe” for children. Larry never even mentioned the risks of adverse developmental effects recognized by ATSDR.

The current “fact sheet” on the Paulsboro website, produced by CTEH – updated on 12/11/12- is still misleading:

Vinyl Chloride

Should I be worried about health impacts from vinyl chloride?
The highest concentrations of vinyl chloride detected are hundreds of times lower than the concentrations that would produce symptoms from the short-term exposures that could occur here.

To be clear, the community monitoring results I report here were taken outside the evacuation zone – this mens the evacuation zone should have been much larger. As I said in the South Jersey Times on December 7, 2012

“I believe that, if I were in charge, there would’ve been a broader and earlier evacuation,” said Wolfe, who stated he was forced out of the DEP for “blowing the whistle” and revealing the department’s scientific research. “The (chemical) exposure should be zero. Why take a risk that’s unnecessary? ... and they should have given the correct expectations to people right away. if you don’t know, say that you don’t know. Be consistent. Be up front with people.”

This raises several question about how these errors and misleading statement were made and continue to be made:

Who produced the false and misleading fact sheets?

What was the scientific basis for DEP’s December 5 false statement quoted above?

Who provided scientific advice to the DEP press office?

Did hired gun CTEH produce the fact sheet? The advice to DEP? Evacuation?

What was the basis and risk level for defining the evacuation zone?

Who provided the scientific health effects info to define the evacuation zone?